This invention relates to reinforced hose couplings and assemblies, and to a method of forming the same, and particularly relates to the coupling of heavy duty hose having multiple plies of reinforcement.
In the design of coupling assemblies for fairly heavy duty hose, for instance rotary drill, choke and kill and motion compensator hose, aside from end seal reliability, an important criteria is the reduction in length and weight of the coupling without compromising working and burst pressure capability. One approach that has been taken is to taper the coupling sleeve into a frustro-conical shape with an enlarged end adjacent the nipple of the coupling. At the base of this frustrum, the pitch of certain of the wire reinforcements has been increased in stepped fashion with the individual wires of increased pitch being longitudinally and/or radially uniformly spaced apart, and then embedded in an anchoring matrix of polymeric material, such as epoxy resin. The taper of the cone and anchoring of the spread wires maintains attachment between the hose and coupling under normal operation.
Despite the effectiveness of the mentioned frustroconical design, prior coupling assemblies have been bulky and expensive to manufacture primarily because of the special treatment required to spread the wires evenly apart at the base of the frustrum, and the numerous parts utilized in the overall assembly.
In addition to the foregoing statement concerning the prior art, additional relevant references include U.S. Pat. Nos. 2,473,441 (Muller), 2,506,494 (Feiler et al), 2,940,778 (Kaiser) and 3,217,282 (Chevalier et al).